Unit 1 - 3 Flashcards
Define a network?
A collection of digital devices that are able to communicate with one another
Benefits of networks?
Accessing files and share files on multiple devices, sharing data e.g. printer
Drawbacks of networks?
Susceptible to certain cyber attacks, security breaches and it is expensive
What does NIC stand for?
Network interface controller
What does NIC do?
It is a computer HARDware component that implements the electronic circuitry using specific physical layers
What is a network switch?
A physical switch that connects more devices to the same or different networks
What is a benefit of a network switch?
Saves time for businesses
What is LAN?
Local Area Network - A group of computers and devices that share data to a server
Drawback of LAN?
Confined to a specific geographic area?
Define bandwidth?
A measure of the amount of data that the medium can transfer over a given period of time
How does bandwidth affect network performance?
Dependant on how much data is being used which will depend on the speed of HOW MANY devices are on the network
What is a medium (transmission medium)?
How data is carried from one place to another either wired or wireless
How does the number of devices affect network performance?
Network congestion, slower speeds, bandwidth needs to be larger for larger amounts of data and more devices to be on the network without the network being affected
What is a star network?
A local area network (LAN) topology in which all nodes (nodes = any device connected to a network) are directly connected to a common central computer hub/switch.
Give advantages of a star network?
Very reliable, high performing given no data collisions can occur
Give disadvantages of a star network?
Expensive to install, if hub or switch fails all devices no longer have any network
What is WAN?
Wide area network - Spread over a wide geographical area, used to communicate all over the world
Give advantages of WAN?
Large range and can communicate across branches such as banks
Give disadvantages of WAN?
Extremely expensive to have set up across a large area
What is an FTP?
File transfer protocol - Is a file server where you can download and upload files to a network on the PC
What is an email sever and what does it do?
It is permanently online and when logging onto computer it downloads and transmits emails to other email servers
What is a DNS server?
Domain name server - Translates a domain name into an internet address (turns web addresses into IP addresses)
What does the cloud mean?
Generic term for remotely accessed storage
Give 2 advantages of the cloud?
Have the ability to access files from any location or device - Reduced need to make backups because cloud stores back up storage for you
Give 2 disadvantages of the cloud?
You may not know who is accessing your data
You need internet connection to access backup
What is mesh networking?
There is no central hub/switch, instead each node (device) is connected to at least one other node, the nodes act as relays passing on a message between themselves to help the message to its final destination
What are the two types of mesh networking?
Full mesh topology and partial mesh topology
What is the difference between full mesh topology and partial mesh topology?
Full mesh - each node is directly connected to each other node, all interlinked
Partial mesh - Not all nodes are directly connected to one another meaning there are fewer routes for a message to travel
What are the benefits of a wired connection?
Much faster, more reliable, less likely to be exposed to hacking
What are the drawbacks of a wired connection?
Expensive, messy, not ideal for portable devices
What are the benefits of a wireless connection?
Greater configuration flexibility, low maintenance, less expensive
What are the drawbacks of a wireless connection?
Speed is slower, proximity is required, easier to hack
Explain the basics of Bluetooth?
Form of wireless communication that enables different devices to connect, piconet is an ad hoc network that inks a GROUP of wireless devices to a network
Define an IP address?
Unique string of characters that identifies each device using the internet protocol to communicate over a network
What is MAC Addressing and why is it used?
Media access control - a unique identifier that is assigned to a network interface, contains a string of hexadecimal numbers, used to identify a device that has joined the network
What are the 3 types of MAC addressing?
Unicast, Multicast, broadcast
Define encryption?
An algorithm that is used to transform data into cipher text - MORE COVERED IN 1.4
Give 3 types of protocols?
TCP - Transmission Control Protocol that enables communication over the internet
HTTP - Hypertext transfer protocol governs communication between a web server and a client
FTP - File transfer protocol that governs transmissions of files across a network
What is network layering and why is it used?
To break up the sending of messages into separate components and activities so it is easier for receiving device to process.
What are the 4 stages of network layering?
Application - TCP (Transport control protocol) - Network - Link
Describe the 1st layer - Application?
Encodes and decodes the message so that the receiver can interpret it correctly
Describe the 2nd layer - Transport layer?
Breaks down message into small packets, each packet is given a number and the total number of packets is sent in the message so that the receiver can put packets in order to interpret message and see if there is a missing packet
Describe the 3rd layer - Network?
Adds the IP address so that the network knows where to send the message so that the recipient can receive it
Describe the 4th layer - Link layer?
Enables transfer of packets between nodes on a network and between networks
